"cannot display this video mode"

Discussion in 'Gaming and Software' started by theblindking, Feb 10, 2009.

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  1. Help!!!

    The cdr drive on my laptop had just packed up, so I dusted off an old dell box that a mate lent me, bought a monitor, cranked it up but as soon as it has finished booting up I get the above message.

    Dell support have suggested that it is probably a graphics/video card issue, but before I spend anymore money I was wondering if anyone could confirm this for me?
    It's running linux as well. I assume that this shouldn't make any difference(?)

    Cheers
     
  2. It shouldn't make a difference at all. All it usually means is that you've got your resolution set to a mode that the monitor can't handle.

    You'll probably have to edit your x11.conf file from the command line.

    When booting the computer press ctl+alt+f4 i think it is to launch virtual console only session. Login using your user account and then type

    "vi/nano (which ever editor takes your fancy) /etc/x11/X11.conf" (this may have to be done as a superuser using "su or sudo"

    find the line that reads something like

    Section "Screen"
    Identifier "Screen0"
    Device "Videocard0"
    Monitor "Monitor0"
    DefaultDepth 16
    SubSection "Display"
    Depth 16
    Modes "1024x768"
    EndSubSection


    change the "Modes" to something small like 800x600 or what you know your monitor supports.

    save this file and restart the X server by pressing ctl+alt+backspace or by shutting down the machine and restarting it by typing "shutdown -h now" this will power the machine down without powering it back up again.


    If the mode you tried doesn't work then you should repeat the above with a different resolution.

    This info should work for most distros.
     
  3. Thanks for the response but it's not that.

    My current setting is 720x400 and the monitors optimum is 1024x768
     
  4. Are you taking the video feed from the onboard adapter or a graphics card?

    Do you have an installation disc, windows or linux. If you can boot off one of those and get a display then somewhere in the configuration for the old linux installtion, it would probably be easier to reinstall a new os.

    If you want to stay with linux and have access to a machine that works you could try

    http://www.ubuntu.com/getubuntu/download

    it's probably the most user friendly distro out there at the min
     
  5. thanks. I'm downloading from Ubuntu now. It's the onboard adapter by the way which was why I was considering the graphics card option
     
  6. Just because your monitor has an optimum of 1024x768 (which implies a standard 4:3 aspect ration monitor) doesn't mean it will necessarily fully support all resolutions lower than that.

    720x400 is a 16:9 widescreen aspect ratio and therefore may not work on a 4:3 monitor (hence the error your getting), especially if its an older one.

    I would still suggest trying to change it as per ex_wobblyheads post but start at something like 640x480 (basic 4:3 aspect ratio setup) which is probably the most basic standard that everything should support.
     
  7. 720x400 is a very odd resolution and that is probably the reason for your problem. Even if you graphics card / monitor supports up to 1024x768 it doesn't mean it will support any resolution below that.

    Try a standard XVGA resolution like 800x600 or 1024x768. Also check the refresh rate, it might be set higher than the graphics card / monitor can handle. If you are using a flat panel monitor then set the refresh rate to 60Hz, if an old CRT start with 70Hz.
     
  8. cheers all.